Apparatus Used in an Electroplating Process for Holding Workpieces

ABSTRACT

An apparatus for holding a plurality of workpieces to be electroplated includes at least one container immersed in and rotatable relative to a plating solution. The container includes two end plates, and a surrounding plate cooperating with the end plates to define a receiving space adapted to receive the workpieces, and an opening adapted for entry and exit of the workpieces into and out of the receiving space. The surrounding plate includes a curved sliding section having two opposite first and second ends, a tumbling section that is adapted to allow the workpieces to tumble thereon when the container is rotated and that has a third end connected to the first end, and a fourth end opposite to the third end, and a plurality of through holes formed in the sliding and tumbling sections. The opening is disposed between the second and fourth ends.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an apparatus, more particularly to an apparatusfor holding a plurality of workpieces to be electroplated.

2. Description of the Related Art

Referring to FIG. 1, a conventional barrel 1 used in an electroplatingprocess is immersed in a plating solution 19 which is contained in aplating tank 18. The barrel 1 is formed with a plurality of throughholes 14 to permit flow of the plating solution 19 there through, andincludes a conductive piece 13 at the center of the barrel 1, a topopening 15, and a cover plate 16 to openably close the top opening 15.Two transmission gears 12 (only one is shown) are respectively providedon two opposite sides of the barrel 1. The barrel 1 has six flatsurfaces 17. Each two adjacent ones of the flat surfaces 17 definetherebetween a specific angle.

When electroplating of small workpieces 10, such as screws, is desired,the cover plate 16 is first opened, and the workpieces 10 are put intothe barrel 1 via the opening 15. Afterwards, the opening 15 is closed bythe cover plate 16. The barrel 1 is then immersed in the platingsolution 19 in the plating tank 18. The transmission gears 12 aresubsequently activated so as to rotate the barrel 1 about a horizontalaxis, thereby plating the workpieces 3.

However, because the workpieces 10 undergo a vigorous tumbling action asthey move from one flat surface 17 to another flat surface 17, and sincethe workpieces 10 are made of metal, when the workpieces 10 bump intoeach other, the surfaces thereof are easily damaged, thereby adverselyaffecting the final quality of the electroplated workpieces 10.

SUMMARY OF THE INVENTION

Therefore, the object of the present invention is to provide anapparatus for holding a plurality of workpieces to be electroplated thatis capable of overcoming the aforementioned drawbacks of the prior art.

According to this invention, an apparatus for holding a plurality ofworkpieces to be electroplated comprises a container unit including atleast one container immersed in and rotatable relative to a platingsolution. The container includes two spaced-apart end plates, and asurrounding plate connected between the end plates and cooperating withthe same to define a receiving space adapted to receive the workpieces,and an opening in spatial communication with the receiving space andadapted for entry and exit of the workpieces into and out of thereceiving space. The surrounding plate includes a curved sliding sectionthat has two opposite first and second ends, a tumbling section that isadapted to allow the workpieces to tumble thereon when the container isrotated and that has a third end connected to the first end, and afourth end opposite to the third end, and a plurality of through holesformed in the sliding and tumbling sections and adapted to permit flowof the plating solution therethrough. The opening is disposed betweenthe second end and the fourth end.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will becomeapparent in the following detailed description of the preferredembodiments with reference to the accompanying drawings, of which:

FIG. 1 is a sectional view of a conventional barrel immersed in aplating solution which is contained in a plating tank;

FIG. 2 is a sectional view of an apparatus for holding a plurality ofworkpieces to be electroplated according to the first preferredembodiment of the present invention;

FIG. 3 is an exploded perspective view of a container of the firstpreferred embodiment;

FIG. 4 is a fragmentary schematic view of the first preferredembodiment, illustrating how rotated plates of the container are incontact with friction wheels;

FIG. 5 is a fragmentary enlarged sectional view of the first preferredembodiment, illustrating the workpieces at a flat plate portion of atumbling section of the container;

FIG. 6 is a view similar to FIG. 5, but illustrating the workpieces at asliding section of the container;

FIG. 7 is a view similar to FIG. 6, but illustrating the workpiecesbeing discharged from the container;

FIG. 8 is a perspective view of an apparatus for holding a plurality ofworkpieces to be electroplated according to the second preferredembodiment of the present invention; and

FIG. 9 is a sectional view of an apparatus for holding a plurality ofworkpieces to be electroplated according to the third preferredembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before the present invention is described in greater detail, it shouldbe noted that the same reference numerals have been used to denote likeelements throughout the specification.

Referring to FIGS. 2 to 7, an apparatus for holding a plurality ofworkpieces to be electroplated according to the first preferredembodiment of the present invention is shown to comprise a containerunit and two pairs of friction wheels 41 only one pair of the frictionwheels 41 or one friction wheel 41 from each pair of the same is shownin the drawings).

The container unit includes a container 3 immersed in a plating solution22 that is disposed in a plating tank 20. The container 3 is rotatablein this state immersed in the plating solution 22. The container 3includes two spaced-apart flat end plates 32, a surrounding plate 31connected between the end plates 32, and two flat rotated plates 33connected respectively and fixedly to the end plates 32 such that theend plates 32 are disposed between the rotated plates 33.

The surrounding plate 31 and the end plates 32 cooperatively define areceiving space 35 (see FIG. 4) adapted to receive the workpieces 21,and an opening 30 in spatial communication with the receiving space 35and adapted for entry and exit of the workpieces 21 into and out of thereceiving space 35. The surrounding plate 31 includes a sliding section341 and a tumbling section 342. The sliding section 341 is curved, andhas two opposite first and second ends 343, 344. The tumbling section342 has a third end 345 connected to the first end 343, and a fourth end346 opposite to the third end 345. The opening 30 is disposed betweenthe second end 344 and the fourth end 346. The tumbling section 342 isadapted to allow the workpieces 21 to tumble thereon when the container3 is rotated, and includes a plurality of interconnected flat plateportions 3421, each two adjacent ones of which form an angle (a)therebetween. The angle (a) is greater than 90°. Alternatively, thetumbling section 342 may include a wave-like plate portion (not shown).As long as the workpieces 21 can undergo tumbling action when thecontainer 3 is rotated, the configuration of the tumbling section 342may be varied, and is not limited to the aforesaid disclosures.

A plurality of through holes 347 are formed in the sliding section 341and the tumbling section 342, and are adapted to permit flow of theplating solution 22 therethrough.

Each pair of the friction wheels 41 is disposed under and in frictionalcontact with a respective one of the rotated plates 33, as best shown inFIG. 4. The friction wheels 41 are driven by a motor (not shown) so asto rotate the rotated plates 33. In this embodiment, the friction wheels41 are used to rotate the container 3. Alternatively, gear wheels may beused to rotate the container 3.

In use, initially, the workpieces 21 are fed into the container 3 viathe opening 30, and are immersed in the plating solution 22. Afterwards,the motor is activated so as to drive the friction wheels 41 to rotatethe container 3. When the container 3 is rotated from a position shownin FIG. 2 to a position shown in FIG. 5, the workpieces 21 in thecontainer 3 tumble from one flat plate portion 3421 to another flatplate portion 3421 due to gravity. Because the workpieces 21 undergo asignificant tumbling action from one flat plate portion 3421 to another,the surfaces of the workpieces 21 are uniformly electroplated.

When the container 3 is rotated from the position shown in FIG. 5 to aposition shown in FIG. 6, the workpieces 21 fall slidingly from the flatplate portion 3421, which is immediately adjacent to the sliding section341, to the sliding section 341. Since the sliding section 341 iscurved, the bumping forces among the workpieces 21 are weakened.Finally, when the container 3 is rotated from the position shown in FIG.6 to a position shown in FIG. 7, the workpieces 21 are completelyelectroplated, and are discharged via the opening 30 to a conveyor belt42.

From the aforementioned description, it is apparent that through theflat plate portions 3421 of the tumbling section 342, the workpieces 21can undergo significant tumbling during rotation of the container 3 sothat the surface of each workpiece 21 may be in contact with the platingsolution 22. As such, the surfaces of the workpieces 21 may beelectroplated uniformly. Further, through the curved configuration ofthe sliding section 341, the work pieces 21 undergo a dampened tumblingaction at the sliding section 341, thereby minimizing the bumping forcesand frictional impact among the workpieces 21. Hence, the quality of theelectroplated workpieces 21 can be enhanced.

Referring to FIG. 8, an apparatus for holding a plurality of workpiecesto be electroplated according to the second preferred embodiment of thepresent invention is shown to be similar to the first preferredembodiment. However, in this embodiment, the two rotated plates 33 (seeFIG. 3) of the container 3′ are replaced by two shafts 37, which areconnected respectively and fixedly to the end plates 32. The shafts 37are driven by a motor (not shown) to rotate so that the container 3′rotates along with the shafts 37.

Since the shafts 37 are used to rotate the container 3′ in thisembodiment, the friction wheels 41 used in the first preferredembodiment are dispensed herein, thereby minimizing the overall cost ofthe present invention. Alternatively, rotation of the container 3′ maybe achieved through other means, and is not limited to the presentdisclosures.

Referring to FIG. 9, an apparatus for holding a plurality of workpiecesto be electroplated according to the third preferred embodiment of thepresent invention is shown to be similar to the second preferredembodiment. However, in this embodiment, the apparatus further comprisesa rotatable frame 5 adapted to be rotatable while at least partiallyimmersed in the plating solution 22. The container unit includes aplurality of containers 3′ connected pivotally to the rotatable frame 5,and are angularly spaced apart from each other. Four containers 3′ areexemplified in this embodiment. The rotatable frame 5 rotates about itscenter. Each of the containers 3′ is rotatable relative to the rotatableframe 5 by the corresponding shafts 37. In this embodiment, when therotatable frame 5 rotates one revolution about its center, eachcontainer 3′ also rotates one revolution along with the correspondingshafts 37. That is, from the initial feeding of the workpieces 21 intoone of the containers 3′ to the second feeding of the workpieces 21 intothe one of the containers 3′, the one of the containers 3′ rotates onerevolution along with the corresponding shafts 37, and the rotatableframe 5 also rotates one revolution about its center. During onerevolution of the rotatable frame 5, each container 3′ is brought toimmerse in the plating solution 22, so that the workpieces 21 can beuniformly electroplated, and can be discharged from the correspondingcontainer 3′ prior to subsequent feeding of the workpieces 21. Hence,not only can the workpieces 21 be uniformly electroplated, but thequantity of the workpieces 21 to be electroplated can be increased aswell.

While the present invention has been described in connection with whatare considered the most practical and preferred embodiments, it isunderstood that this invention is not limited to the disclosedembodiments but is intended to cover various arrangements includedwithin the spirit and scope of the broadest interpretation so as toencompass all such modifications and equivalent arrangements.

1. An apparatus for holding a plurality of workpieces to beelectroplated, said apparatus comprising a container unit including atleast one container immersed in and rotatable relative to a platingsolution, said container including two spaced-apart end plates, and asurrounding plate connected between said end plates and cooperating withsaid end plates to define a receiving space adapted to receive theworkpieces, and an opening in spatial communication with said receivingspace and adapted for entry and exit of the workpieces into and out ofsaid receiving space, said surrounding plate including a curved slidingsection that has two opposite first and second ends, a tumbling sectionthat is adapted to allow the workpieces to tumble thereon when saidcontainer is rotated and that has a third end connected to said firstend, and a fourth end opposite to said third end, and a plurality ofthrough holes formed in said sliding and tumbling sections and adaptedto permit flow of the plating solution therethrough, said opening beingdisposed between said second end and said fourth end.
 2. The apparatusof claim 1, wherein said container further includes two rotated platesconnected respectively and fixedly to said end plates such that said endplates are disposed between said rotated plates, said apparatus furthercomprising two pairs of friction wheels, each pair of said frictionwheels being disposed under and in frictional contact with a respectiveone of said rotated plates and being driven to rotate the respective oneof said rotated plates.
 3. The apparatus of claim 1, wherein saidcontainer further includes two shafts connected respectively and fixedlyto said end plates such that said container is rotatable along with saidshafts.
 4. The apparatus of claim 3, further comprising a rotatableframe adapted to be rotatable relative to the plating solution, saidcontainer unit including a plurality of said containers connectedpivotally to said rotatable frame and angularly spaced apart from eachother.
 5. The apparatus of claim 1, wherein said tumbling sectionincludes a plurality of interconnected flat plate portions, each twoadjacent ones of which form an angle therebetween, said angle beinggreater than 90°.